Rotary engine



(No Model.) 2 Sheets- 81mm 1. r W. SPRAGUE.

ROTARY ENGINE.

No. 262,141. Patented Aug. 1, 1882.

(No Model.) 2 Sheets-Sheet 2.

W. SPRAGUE.

ROTARY ENGINE.-

Patented Aug. 1, 1882.

ATTOPQIEY.

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Usirrnn STATES PATENT fission.

\VILLIAM SPRAGUE, OF PHILADELPHIA, PENNSYLVANIA.

ROTARY ENGINE.

SPECIFICATION forming part of Letters Patent N0. 262,141, dated August1, 1882.

Application filed March 22, 1881.

To all whom it may concern Be it known that I, WILLIAM SPRAGUE, acitizen of the United States, residing in the city and county ofPhiladelphia, and State of Pennsylvania, have invented a new and usefulImprovement in Rotary Engines, which improvement is fully set forth inthe following specification and accompanying drawings, in which Figure lis a side elevation of the rotary engine embodying my invention. Fig. 2is a horizontal section of a portion thereof in line mm, Fig. 1. Fig. 3is a vertical section thereof in, line y y, Fig. 2. Fig. 4 is a view ofa detached part.

Similar letters of reference indicate corresponding parts in the severalfigures.

My invention consists of a rotary compound steam-engine adapted to runat a high degree of speed and with increased effectiveness, and

provided with reversing mechanism, the construction and operationthereofheing hereinafter fully set forth.

Referring to the drawings, A represents a small cylinder, and B a.larger cylinder,

which are suitably flanged and bolted or otherwise connected together,and though independent of each other are in communication by means ofpipes (J, each of which is provided 0 with a check-valve, C, alsoconstituting astop-valve.

\Vithin the cylinder A is a piston-wheel, l), and within the cylinderBis apiston-wheel, E, the two wheels being fixed on a shaft, F, which ispassed centrally through the heads of the two cylinders and carries thepulley G, by which the power of the engine may be utilized ortransmitted to machinery.

The cylinder A is provided with a valve and valve mechanism, with liveand exhaust steam ports, as at H, and the cylinder B is similarlyprovided, as at J, a steam-supply pipe, K, leadingto the valve mechanismH, and a steamsupply pipe, L, leading to the valve mechan- 4 5 ism J,each supply-pipe having a cook, a.

The wheels are each provided with a piston, M, on the periphery thereof,that M of the wheel E being shown by the dotted lines, Fig. 3.

N represents the abutment-blocks, one for (No model.)

each cylinder, the same being fitted between the walls of the ports a,and bearing against the periphery ofthe wheel, and havingan openinginwhich is fitted an eccentric, P, the shaft of which passes through thehead of the cylinder, and carrying on its outer end a pinion, b, whichgears with a spur-wheel, c, properly mounted on the outer walls of thevalve mechanism, and having pivoted to its wrist-pin d ajointed arm, Q,one limb of which is pivoted to the head of the cylinder, and carries atits outer end a'stud or pulley, 0, adapted to be engaged atin tervals bya cam f,on oracamgroove in the pulley G, so that rotation is imparted tothe wheels 0 b, and consequently to the eccentric P, whereby theabutment-block will be moved from the periphery of the piston-wheel toallow the passage of the piston M, and atterward again moved againstsaid periphery as the closing point of the wheel.

On the outer ends of the shaft F are eccentrics It, the surrounding yokeR of each of which is connected to an arm, S, whose upper end isadjustably fitted to a rocking lever, T, the shaft T whereof is mountedon standards T, rising from the frame or cylinders of the engine, therocking lever T having segmental slots 9 to receive blocks to which thearms S are pivoted, and formed with notches into which drop theholding-teeth of said arms S, the teeth being adapted to be raised toclear the notches of the lever T, and when the arms are moved oradjusted the teeth dropinto'the respective notches, and so hold the armsin position.

. The outer ends of the rocking lever T are removably connected to theupper ends of the stems U of the valves of the two cylinders, and saidends V are hinged or swiveled to the main portions of the stems andformed with hooks V for the reception of pins or studs on the ends ofthe rocking lever T. To the hooked ends V are pivoted levers W, somewhatof the order of toggle-levers, the central connectingpivots of which areattached to a sleeve, W, which is fitted on a collar, X, supported onthe standard T. A spring, X, is placed within the collar and sleeve, andrests on the top of the standard and bears upwardly against the sleeve.A catch, Y, with a proper handle, is 100 ,cylinders then taking livesteam.

from cylinder A exhausts at the proper port of 5 its valve mechanism H,and that from cylin- ,der B at the proper port of the valve mechan- 2the valve-stems U, thus disengaging the rocking lever. The latter isthen raised or lowered to enter the upper or lower hooks, and the catchY is released, and the spring X raises the sleeve WV and with it thearms WV, thus drawing in the ends V, so that the hooks again engage withthe rocking lever, these features being employed when the engine is tobe reversed.

In starting the engine both cocks a a. are opened and both checkvalves Cclosed, both The steam ism J.

Should less power be required, steam is shut off from the cylinder B byclosing the proper cock a The opposite check-valve U is opened. Steamfrom the cylinder A then passes into the cylinder B and works thereexpansively; or steam from the cylinder A is shut otf, the opposite cockat is closed, and the opposite checkvalve is opened and the othercheck-valve is closed, live steam then entering the cylinder B,and,passing into the cylinder A, works there expansively.

It will be seen that the steam acts upon a piston of certain area andrevolves the shaft F. After a half-revolution of the shaft or piston thesteam is cut off and allowed to act upon the piston in the othercylinder at the same time with the first cylinder. At this moment thereis steam of the same pressure on both pistons. The steam begins toexpand, and, giving the area of the piston in the second cylinder theproper proportion at the end of the next half-revolution, the samepressure will be on the pistons as there was originally on the firstcylinder alone. When the piston passes the port a the cylinder Aexhausts and the check-valve O closes quickly, owing to the pressure onits under side being released by the exhaust. The steam follows thepiston of cylinder B until it arrives at its exhaust-port. In themeanwhile the piston of cylinder A has arrived at its steam-port, and

the second cylinder exhausts ahead and takes live steam from the boiler.

The power gained through the expanding steam in the second cylinder isan actual gain over the live steam admitted to the first cylinder fromthe boiler, and the pressure willv be equalized on both pistons.

During the operation and running of the engine the exhaust-ports of bothcylinders are constantly open to the atmosphere, so that there is noback-pressure on the piston-to overcome the slide-valves, which arebalanced.

The steamehests and their valves are so arranged and timed that steam isentirely cut off from the cylinders while the pistons pass theabutment-blocks.

The check-valves C have their stems of two parts, fitting each othertelescopically, whereby when the upper stem of a valve is fully loweredthe valve proper is forced on its seat as a stop-valve, and when saidstem is raised the valve proper is adapted to rise and fall as acheck-valve.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is-

1. In a rotary engine, the combination of the concentric piston wheelsand the movable abutment-blocks with two pistons and cylinders ofdifierent areas on the same shaft, :1. communicating pipe, and acompound check and stop valve, live steam being supplied to one cylinderand passing thence as exhauststeam to the other cylinder, substantiallyas set forth.

2. The combination, with the eccentrics, of the arms S, the rockinglever T, with slots g, and the valve-stems, substantially as and for thepurpose set forth.

3. The hooks V of the stems U, and levers WV, in combination with collarX and sleeve Msubstantially as and for the purpose set forth.

4. The coinbination,with the levers W, collar X, and sleeve \V, of thecatch Y and spring X, substantially as and for the purpose set forth.

5. The combination of double cylinders, valve mechanism, and reversingmechanism, constructed and operating substantially as and for thepurpose set forth.

JOHN A. \VIEDERSHEIM, A. P. GRANT.

